TOPEKA (KSNT) – With the start of summer, some lakes around the state are beginning to look a little greener than usual.

If you’ve noticed that your local lake or reservoir isn’t looking quite right, that could be because of the presence of blue-green algae. Every year, this algae appears in lakes across Kansas as a nuisance or, in some cases, a public health hazard. The presence of the algae can lead to the appearance of a dangerous harmful algal bloom (HAB).

The Kansas Department of Health and Environment (KDHE) say on their website that a HAB can appear like foam, scum or paint floating on the water. It can be a variety of colors like blue, bright green, brown or red. A bloom is hazardous to both people and animals, as it produces toxins that can be absorbed by ingestion, inhalation and skin contact.

Exposure to a HAB can include a rash, vomiting, diarrhea, fever, sore throat and a headache, according to the KDHE. People and animals that come into contact with an HAB are recommended to rinse the impacted area clean with fresh water. HAB-related incidents can be reported online by clicking here.

The algae comes from a “perfect storm” of conditions, according to KDHE Director of the Bureau of Water Tom Styles. A combination of plentiful nutrients, calm conditions and warm temperatures create an environment where the algae and HABs can form. The presence of some invasive species, like the notorious zebra mussel, can also cause HABs to appear.

Lakes in Kansas can be designated by one of three different levels if blue-green algae or a HAB are found in their waters by KDHE staff: Watch, Warning and Hazard. The KDHE recommends different precautions to those who might come into contact with lakes afflicted by the algae:

  • Watch
    • Signage should be posted at all public access locations.
    • Water may be unsafe for humans/animals. 
    • Avoid areas of algae accumulation and do not let people/pets eat dried algae or drink contaminated water. 
    • Swimming, wading, skiing and jet skiing are discouraged near visible blooms. 
    • Boating and fishing are safe. However, inhalation of the spray may affect some individuals. Avoid direct contact with water, and wash with clean water after any contact. 
    • Clean fish well with potable water and eat fillet portion only. 
  • Warning
    • Signage should be posted at all public access locations.
    • Inhalation of spray or aerosols may be harmful.
    • Lake water is not safe to drink for pets or livestock.  
    • Lake water, regardless of blue-green algae status, should never be consumed by humans.  
    • Water contact should be avoided.  
    • Fish may be eaten if they are rinsed with clean water and only the fillet portion is consumed, while all other parts are discarded.  
    • Do not allow pets to eat dried algae.
    • If lake water contacts skin, wash with clean water as soon as possible.  
    • Avoid areas of visible algae accumulation.  
  • Hazard
    • Signage should be posted at all public access locations.
    • It is recommended that either a portion of the lake or the entire lake or zone be closed to the public.
    • In some cases, the adjacent land should be closed as well. Actual setback distances will be determined on a site-specific basis, if necessary.
    • When partial closures (i.e., beach or cove) are issued, the remaining lake or zone area will carry a warning status.

The KDHE regularly samples waterbodies for the presence of algae or HABs. Lakes and reservoirs can reach an elevated status, fall to a lower status or have their blue-green algae advisory lifted. For a list of all impacted waterbodies, click here.